[PATCH v2] drm/amd/display: Add debugfs entry for amdgpu_dm_visual_confirm

[Li, Sun peng (Leo)]

On 2019-03-22 10:11 a.m., Nicholas Kazlauskas wrote:
> [Why]
> DC provides a few visual confirmation debug options that can be
> dynamically changed at runtime to help debug surface programming issues
> but we don't have any way to access it from userspace.
> 
> [How]
> Add the amdgpu_dm_visual_confirm debugfs entry.
> It accepts a string containing the DC visual confirm enum value using
> the debugfs attribute helpers.
> 
> The debugfs_create_file_unsafe can be used instead of
> debugfs_create_file as per the documentation.
> 
> v2: Use debugfs helpers for getting and setting the value (Christian)
> 
> Cc: Leo Li <sunpeng.li at amd.com>

Reviewed-by: Leo Li <sunpeng.li at amd.com>

Thanks,
Leo

> Cc: Harry Wentland <harry.wentland at amd.com>
> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>
> ---
>   .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 39 ++++++++++++++++++-
>   1 file changed, 38 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> index 1a9e3d3dfa38..1d5fc5ad3bee 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> @@ -995,6 +995,35 @@ static const struct drm_info_list amdgpu_dm_debugfs_list[] = {
>   	{"amdgpu_target_backlight_pwm", &target_backlight_read},
>   };
>   
> +/*
> + * Sets the DC visual confirm debug option from the given string.
> + * Example usage: echo 1 > /sys/kernel/debug/dri/0/amdgpu_visual_confirm
> + */
> +static int visual_confirm_set(void *data, u64 val)
> +{
> +	struct amdgpu_device *adev = data;
> +
> +	adev->dm.dc->debug.visual_confirm = (enum visual_confirm)val;
> +
> +	return 0;
> +}
> +
> +/*
> + * Reads the DC visual confirm debug option value into the given buffer.
> + * Example usage: cat /sys/kernel/debug/dri/0/amdgpu_dm_visual_confirm
> + */
> +static int visual_confirm_get(void *data, u64 *val)
> +{
> +	struct amdgpu_device *adev = data;
> +
> +	*val = adev->dm.dc->debug.visual_confirm;
> +
> +	return 0;
> +}
> +
> +DEFINE_DEBUGFS_ATTRIBUTE(visual_confirm_fops, visual_confirm_get,
> +			 visual_confirm_set, "%llu\n");
> +
>   int dtn_debugfs_init(struct amdgpu_device *adev)
>   {
>   	static const struct file_operations dtn_log_fops = {
> @@ -1020,5 +1049,13 @@ int dtn_debugfs_init(struct amdgpu_device *adev)
>   		adev,
>   		&dtn_log_fops);
>   
> -	return PTR_ERR_OR_ZERO(ent);
> +	if (IS_ERR(ent))
> +		return PTR_ERR(ent);
> +
> +	ent = debugfs_create_file_unsafe("amdgpu_dm_visual_confirm", 0644, root,
> +					 adev, &visual_confirm_fops);
> +	if (IS_ERR(ent))
> +		return PTR_ERR(ent);
> +
> +	return 0;
>   }
>